Basic derivatives of alpha-substituted aryloxy acetic acids and a process for their manufacture



Patented Oct. 14, 1947 Henry Martin and Franz Hiifliger, Basel, Switzerland, assignors to J. R. Geigy A. G.,

OF (It-SUBSTITUTED Basel,

Switzerland, a Swiss firm No Drawing. Application July 28, 1944, Serial No. 547,100. In Switzerland July 30, 1943 Basic esters and amides of aryloxy acetic acids which are useful for therapeutical purposes have not yet become known heretofore. On examination of basic esters of phenoxy acetic acid, of diphenoxy acetic acid and of phenoxy isobutyric acid with regard to their spasmolytic eflicacy there has been observed no spasmolytic effect (of. B. N. Halpern, Arch. intern. Pharmacodynamie, 59, 188 (1938).).

Incontradistinction thereto we have now surprisingly found that basic esters and amides of lat-substituted aryloxy acetic acids of the general wherein R1 stands for an aromatic radical of the benzene or naphthalene series, and, more particularly, a phenyl, alkylphenyl, alkoxyphenyl,

diphenyl, phenoxyphenyl or-chloropheny1 radical,

X stands for a lower alkyl group, cycloalkyl group,

or an aromaticradical of the benzene series, more particularly, a phenyl or tolyl radical,'Y stands, X and Y for hydrogen or a lower alkyl group, stand jointly for a tetramethylene or pentamethylene group, A stands for -O, in the case of the esters, and for -NH or a -N-lower-alkyl group, in the case of the amides, R2 stands for a low molecular alkylene group, and Am means the radical of a secondary amine, more particularly, a dialkylamine, piperidine or morpholine, possess valuable-therapeutical properties. These. products are distinguished by a good spasmolytical eflicacy and possess musculotropic, papaverinelike effects as well kind of atropine. In connexion therewith there may be pointed out that the new products show not at all or only in a small extent the mostly undesiredby-effects of atropine. Furthermore,

many of the new compounds show a manifest analgetic efiicacy. a

The manufacture of the claimed esters can be carried out according to different methods. For example, reactive derivatives of the above defined aryloxy acetic acids, such as their halides, esters or anhydrides are interacted with N-disubstituted amino alcohols in the presenc'e'or absence of condensation agents; another method consists in that reactive esters of the aminoalcohols, especially hydrogen halide esters, aryl sulfonic acid esters and the like, are caused to react, if necessary in the presence of acid binding agents, with the said acids or their salts respectively.

' Moreover, it is also possible'to convert the caras a neurotropic activity of the I 5 Claims. (Cl. 260-473) 2 boxylic acids in the usual manner. into their halogen alkyl estersand to cause the latter to react with secondary amines.

For the preparation of the basic amides the said acids or their functional derivatives are for instance interacted with alkylene diamines containing a primary or secondary amino group as well as a tertiary amino group. A further method consists in that salts, especially alkali salts of corresponding carboxylic acid amides, are caused to react with reactive esters of amino alcohols. The basic amides can also be obtained by first preparing the halogen alkyl amides of the carboxylic acids in question and reaction of the latter with secondary amines.

The basic esters and amides may, furthermore,

also be obtained in the following way: Compounds of the general formula z-on-o OARz-Am wherein Z means a reactive atom or an exchangeable atom grouping, Am, A, R2, X and Y having the above meanings, are interacted with compounds of the general formula Ri-OH wherein R1 has again the above meaning, or with their salts, if desired in the presence of acid binding agents. As reactive atoms or atom groupings, there may be enumerated: halogen, alkoxy, benzyloxy, sulfonic acid ester groups and so on.

The u-substituted aryloxy acetic acids are partly known; in any event, they may be obtained according to the methods described in the literature.

The basic esters and amides in form of their salts with inorganic or organic acids, are watersoluble and give neutral aqueous solutions. The quaternary compounds of the esters and amides can be obtained in the usual way.

The claims of the present application are directed exclusively to the a'forediscussed esters, which, when R1 is phenyl or substituted phenyl as above indicated, constitute the presently-preferred species of the invention.

The present invention will now be illustrated, but not limited by the following examples, the

parts beingby weight unless otherwise stated.

EXAMPLE 1 21.2 parts of a-phenoxy isovaleric acid chloride are dissolved in 250 partsby volume of absolute ether and cooled below 0 0, While continuously cooling and stirring, a solution of 13 parts of diethyl amino ethanol in 50 parts by volume of absolute ether is dropped thereinto. Then the whole mixture is stirred for 1 hour at room temperature and the reaction mixture is shaken twice with water and once with diluted hydrochloric acid. The combined aqueous solutions are made alkaline to phenolphthaleine and the base thus separated is extracted with ether. The ethereal solution is Washed with Water, dried over Potassium carbonate and the solvent is distilled off. The obtained a-phenoxy isovaleric acid diethyl amino ethanol ester of the formula boils at 128-130 C. at 0.1 mm. pressure.

If instead of the m-phenoxy isovaleric acid chloride, in the above example other aryioxiy acetic acid chlorides are used, the following basic esters are obtained:

R1o( H-o o 0121201190 /.C]\I G aHn CH:

maze 1 No. 7 In I B. 1? mm iii Table 1-Continued No. R; B. P mm.

EXAMPLE 2 22.8 parts of a-(m-chlorophenoxy)-isovalerlc acid are dissolved in 250 parts by volume of dry acetic ester, then heated with 15 parts of =5- chloro'ethyl diethyl amine and 15 parts of potassium carbonate and the whole is stirred for '24 hours at its boiling temperature. After cooling the inorganic residue is filtered off and washed with acetic ester, whereupon the combined filtrates are repeatedly extracted with diluted hydrochloric acid. The acid aqueous solution is extracted with ether, then made alkaline to phenolphthaleine and the base thus separated is again extracted with ether. After drying over potassium carbonate the ether is distilled off. By a further distillation of the residue u-(mchlorophenoxy)-isovaleric acid diethyl amino ethanol ester of the formula on: be. is obtained; this product boils at 0.07 mm. pressure at 134-136 C. v

In the same manner the following compounds may be obtained:

CiHa

R1=0o-H=-o 0 0 iomomN 1 "H Cam CH: on,

Table 2 No. R1 13.? "0.

3 (smog 1 30-132- 0.07

'C2Hz' OzHs I o cimo na-151 0.0a

8 parts of glycol chlorohydrine are dissolved in 100 parts of dry pyridine. Then, while stirring, 2.3 parts of oz-(O-CI'ESOXY) -isova1eric acid chloride are dropped into this solution, the reaction temperature being maintained below C. Now, the whole is poured onto ice, made acid to Congo red and extracted with ether. After washparts of diethyl amine and heated in the auto- 7 clave for 6 hours to -120 C. by working up the mixture according to the indications of Example 2 one obtains a-(O-CIBSOXY) -isova1eric acid diethyl amino ethanolester (see Table 1, compound No. 1)

EXAMPLE 4 25.6 parts of the dry sodium salt of a-(m-cresoxy)-cyc1openty1 acetic acid are powdered until a dust-like powder has resulted. The same is then suspended in 200 parts by volume of absolute benzene. After addition of 15 parts of 3-ch1oro-ethy1 diethyl amine the mixture is heated. to boiling for 12 hours, the mixture being stirred during this operation. The new base of of the formula OCH-C oo oHrom-N CH3 CzHs is worked up as described in Example 2. It possesses the boiling point of 136-138 C. at 0.0-8

mm. pressure. I

According to the same methods the following compounds can be produced:

ing, drying and distillation of the ether the a-(o- V 04134 cresoxy) -isovaleric acid-p-chloroethyl ester, B. P.

. RO-OHOO0GH on N -110 C. at 0.1 mm. pressure, is obtained. A) 2 2- 13.5 parts of this compound are treated in Q @1155 100 parts by volume of absolute toluene with 8 x Y Table 3 No. R1 11 'Y B.P. mm.

2 'C2H5 CH1 133-135 0.1

s C2Ha 02115- 138-140 0.08

4 olm- 11-00211 143-145 0.1

CHs 0 o1 1 H 132-135 0.05

0 -oH,-o11- -CH CH 142-144 0.12

7 Q -OHz-CH CHr-CHz- 138-140 0.05

@- -oH4-oH4-oH4 -CHzCH4-. 142-144 0.02

No. R1 'Y I B.]? mm.

abov examl fl-n EXAMPLE e p e, the o1 0W1 g compounds W111 be When starting from 23 parts of'a-(m-oresoxy') isovalerio acid chloride and parts of dimethyl amino ethanol there is obtained, according to Example 1, the u-(m-ciesoiiy)--is'ovaleric acid dimethyl amino ethanol ester of the formula obtained B. P. -155-156-C.at-0;3 mm. pressure.

om O O @0-011-0 0 0 CHrCH1CHz-N\ H CH; 40 CH CH: vZ

CHI CH:

'BIP. 1"36138 C. at 0.2 mm. pressure.

. 1 R OCHC o R -B. P. 11-8-120 C. at 0.1 mm. pressure. M x a If, instead of dimethyl amino ethanol, other g amino alcohols or acid chlorides are used in the CH9 CH3 Table 4 -'-N'i). R1 R1 B. P mm 1 0. 1 Q -0-0H,0H1Nj 144-146 0.1

-o OHFCHFN 139-140 0.15 CH3 3 -OCHzCHz-N 165-168 0.35

*4 -O-CHzCHzCHz-N -132 0.05

CzHs 5 OCHrCH2-CH2.N 131-133 0.15

CzHg OH:

1 CH: C2H6 I a I OCH2-C-CH2 138-140 0.1

CH9 02H CH:

Table 4-Continued No. R; R: 13.1 mm.

. w. 7 -OCH -CHz--OHz-N\ 148-150 0.08

. s -OOH:CHr-CHa-N 145-146 0.15

/GHz 7 9 -OCH,CHz-CH:-N re-12o 0.1a

CH CH3 EXAMPLE 6 140 parts of u-bromo isovaleric acid diethyl amino 21.2 parts of a-PhBHOXY valeric acid chloride are interacted according to the indications made in Example 1, with 13 parts of N:N-diethyl ethylene diamine, thus giving, after a usual working up, the base of the following formula B. P. 150-153 C., at 0.03 mm. pressure.

In the same manner the following compounds may also be obtained:

CH: CH:

B. P. 148-150 C., at 0.1 mm. pressure.

CgHs O(JHCONCHz-CHrN CH CHa CH3 CH3 B. P. 138140 C. at 0.1 mm. pressure.

CH: CHa B. P. 150-l52 C. at 0.1 mm. pressure, is isolated.

EXAMPLE 8 CzHs CzHs OH:

81 parts of dry guaiacol potassium salt are suspended m 500 parts by volume of xylene, then ethanol ester (B. P. 95-100 C. at 0.4 mm. pressure) are added and the whole is heated to boiling for 4 hours under stirring. After cooling the residue is filtered by suction, washed with xy lene and the xylene is distilled in vacuo. The residue is dissolved in diluted hydrochloric acid, extracted with ether and, the new'base separated by means of a sodium carbonate solution. The base is extracted with ether, washed and dried over potassium carbonate. After distilling off the ether there will be obtained in a good yield, by further distillation, the oz- (o-methoxyphenoxy) -isova1eric acid diethyl amino ethanol ester of the formula C2115 CH3 B. P. 135-137 C. at 0.1 mm. pressure.

Instead of the bromo compound used in the above example, the analogous chloro compound or another ester-like compound, such as the toluene sulfonic acid ester, may be used; moreover, also ether-like compounds, such as the analogous methoxy or benzyloxy compounds, are suitable.

What we claim is: r

1. A basic derivative of an a-substituted aryloxy acetic acid of the formula wherein It represents a member selected from the group consisting of phenyl, methylphenyl and methoxyphenyl, Z represents a member selected from the group consisting of /CH3 CH3 -CH 1 CH3 C2115 CHa-CH: OHz-OH:

--CH and OH CH:

Am represents a radical selected from the group consisting of dialkylamino, piperidino and morpholino radicals, and 12 means one of the integers 2 and 3, being a colorless liquid of valuable thera- V peutical properties.

2. A basic ester of an a-Sllbstitlltfid aryloxy acetic acid of the formula 11 12 3. The basic ester of a a-substituted aryloxy 11 acetic acid of the formula Q O /C 2H5 (IJH (h s QO(?HCOOCHrCHr-N\ 5 CH3 0E3 CHz 0E C'iHt being a colorless liquid of valuable therapeutical g properties. I l

CHPCH l0 FRANZ HZ'KFLIGER. being a colorless liquid of valuable therapeutical I REFERENCES CITED ro er 1es. p LpThe basic ester of an Wsubstituted aryloxy The following references are of record in the acetic acid of the formula file of thls patent:

' 02m 15 UNITED STATES PATENTS Number Name Date 2,010,731 Lubbert et a1. Aug. 6, 1935 Cm f g Cam 1,987,546 Blankart Jan. 8, 1935 CHE CH5 20 OTHER REFERENCES being a colorless liquid of valuable t'herapeutical Halpern, Arch. intern. Pharmaeo-dynamie, properties. vol. 59, pp. MiG-151,156, 188 (1938).

5. The basic ester of an lat-substituted aryloxy Plazek et aL, Chemical Abstracts, vol 30 acetic acid of the formula (1936), p. 1371'. 

